1. Field of the Invention
THE PRESENT INVENTION relates to an air-bag arrangement, and more particularly relates to an air-bag arrangement for use in a motor vehicle such as a motor car.
2. Description of Related Art
It has been proposed to provide an air-bag arrangement in the form of a so-called inflatable curtain, to provide protection for an occupant of a motor vehicle in the event that an accident such as a side impact, or a roll-over situation should occur. Air-bags of this type are described in many prior Specifications including GB 2,297,950A.
The air-bags or inflatable elements which form the so-called inflatable curtains are typically formed to have two adjacent layers of fabric, with selected regions of the fabric layer being interconnected, or even inter-woven using a one-piece weaving technique, so that the air-bag presents a plurality of separate inflatable zones, regions, chambers or cells.
This particular construction for an inflatable curtain is preferred, because the inflatable curtain is normally initially stored in a housing or recess which extends over the door openings of the motor vehicle, and which is therefore not straight, but curved. It is desirable for the air-bag, when inflated, to become tensioned, since otherwise if the head of an occupant strikes the air-bag, when it is located adjacent a window, the force applied to the air-bag by the head of the occupant may cause the window to break, and the air-bag may then pass through the broken window permitting the head of the occupant to move to a position on the exterior of the vehicle.
Consequently, in the prior proposed arrangements, the air-bag has had an upper edge secured to part of the vehicle located above the door opening, and at least one strap extending from the lower edge to an anchoring point provided, for example, on the “A”-Post or on the “C”-Post of the vehicle. In some cases there is no strap, but the lower edge of the inflatable element is itself secured to the anchoring point.
The use of a strap is preferred, since it does facilitate the initial storage of the inflatable element within the recess or housing. It is to be understood, here, that the opposed ends of a line of tension that is to be created as the air-bag inflates, are always firmly secured to the motor vehicle, and the inflatable element and any straps must be stored in the recess or housing which has a length much greater than the length of the line of tension, because the recess or housing is not straight. Thus, it is important that the effective length of the air-bag (and any associated strap) extending between the two anchoring points which define the opposed ends of the line of tension should reduce as the air-bag is inflated. The effect of the zones, regions, chambers or cells, foiled by the regions of fabric which are secured together, provides the effect of reducing the length of the relevant part of the air-bag.